This relates generally to wireless electronic devices and, more particularly, to testing of wireless electronic devices.
Wireless electronic devices typically include transceiver circuitry, antenna circuitry, and other radio-frequency circuitry that provide wireless communications capabilities. During testing, wireless electronic devices under test (DUTs) can exhibit different performance levels depending on whether each DUT has been properly designed and manufactured. For example, each wireless DUT in a group of DUTs can exhibit its own output power level, gain, frequency response, efficiency, linearity, dynamic range, downlink sensitivity, etc.
The uplink and downlink performance of a wireless DUT can be measured using a radio-frequency (RF) test station. An RF test station typically includes a test host, a tester (i.e., a signal generator/analyzer), and a shielded box (often referred to as a test cell). The tester is connected to the test host. Connected in this way, the test host can configure the tester to transmit downlink radio-frequency signals during test operations.
In conventional radio-frequency test arrangements, a wireless DUT having, for example, a cellular telephone transceiver configured to operate using a Code Division Multiple Access (CDMA) wireless communications protocol may be placed into the test cell. The DUT is connected to the test host via a Universal Serial Bus (USB) cable (i.e., the DUT is “tethered” to the test host). A protocol-compliant connection is established between the tester and the DUT (i.e., radio-frequency signals are conveyed between the tester and the cellular telephone transceiver of the DUT using the CDMA protocol). Depending on test results gathered using the tester, a test operator may determine whether the DUT satisfies design criteria.
Electronic devices that are operable across different wireless communications protocols have recently been developed (e.g., electronic devices containing wireless communications circuitry capable of supporting cellular telephone protocols such as the Long Term Evolution (LTE) protocol, Global System for Mobile Communications (GSM) protocol, Code Division Multiple Access (CDMA) protocol, Universal Mobile Telecommunications System (UMTS) protocol, etc.). Conventional test methods and equipment, however, are only capable of testing the operation of a DUT operating using a subset of existing communications protocols and are incapable of testing the operation of the DUT across all wireless communications protocols. For example, only transitions between CDMA and LTE and only transitions between UMTS and LTE are supported. Testers that support such transitions in testing are expensive and require unacceptably long test times. Moreover, the presence of the USB cable that is connected to the DUT during conventional test arrangements reduces the accuracy of radio-frequency test measurements.
It would therefore be desirable to be able to provide improved ways for performing over-the-air testing.